Справочник Пользователя для Mitsubishi Electronics MELSEC -Q/L

7  APPLICATION INSTRUCTIONS

7.19  Other Instructions

*1 Only strings can be used

Processing details

 • The string data specified by (S) is displayed as a user message in the display unit. The string specified directly by (S) 

(surrounded by double quotation marks (")) or the string from the device number specified by (S) until the device number 
storing "00H" is displayed.

 • Strings of up to 128 single-byte characters can be displayed in the display unit.
 • The user message is displayed when the UMSG instruction command is rising. If the string is changed while the command 

is on, then the modified user message will appear in the display unit.

 • The string specified by the UMSG instruction is displayed upon END processing. If two or more UMSG instructions are 

executed, then the last UMSG instruction executed before the END is valid. If two or more programs are running, then the 
last UMSG instruction to be executed is valid.

 • This instruction is not processed if it is run when no display unit is mounted.
 • If the "ESC" key on the display unit is pressed while a user message is being displayed, the displayed message will 

disappear. To display the message again, execute "User Message" from the menu screen on the display unit.

 • If a NULL code (00H) is specified as the argument to this instruction, then any message currently being displayed will 

disappear. The procedure for specifying a NULL code (00H) in the instruction parameter is as follows.

 • See the MELSEC-L CPU Module User's Manual (Function Explanation, Program Fundamentals) for details about the 

display unit.

• Built-in Ethernet port LCPU: Supported
• L02SCPU and L02SCPU-P cannot be used.

(S):   String to display on display unit, or lead number (string) of device storing string to display

J\

U\G

(S)









Universal

Basic

High

performance

Process

Redundant

UMSG

S

Command

b15  to  b8

b7  to  b0

2nd char

1st char

4th char

3rd char

6th char

5th char

8th char

7th char

10th char

9th char

Run UMSG 
instruction

00

Indicates end of string.

Message appears 
on display unit.

S

+1

+2
+3

+4

S

S

S

S

H

User message

Process A complete.

Specifying a NULL code(00

H

)